Although it sounds like a country in the eastern hemisphere, it is a term for severe eyestrain. Asthenopia is caused from weakness in the visual system, including the visual cortex of the brain. It can lead to any of the following symptoms: headaches, sleepiness, poor concentration, light sensitivity, nausea, temporary blurred vision, burning eyes, difficulty reading, irritability, and pain.
Poor focus or need for eyeglasses is the most common cause. Uncorrected focus power or unequal prescription triggers the eye muscles to work extra hard for reading, computer, or smart-phone use. Subconsciously, the brain gets confused and manifests into the problems listed above. The correct spectacle power can be a quick fix. Wearing proper spectacles will not cause the eyes to get weaker or become dependent. Often, there is a superstitious connection made about dependency on glasses and unnecessary suffering follows.
Binocular vision problems or eye muscle alignment is a close second cause. Often it is under diagnosed at an eye examination. If the eyes cross, turn out, or have misalignment vertically, the brain gets confused about where and how to concentrate. Careful positioning of the optical lens centers or prism built into the spectacles can fix the problem. Premade spectacles, known as cheaters or magnifiers, can’t possibly correct for eye alignment problems the way custom lenses can. Prism can bend the light to alleviate eyestrain or even double vision caused from imperfect eye positioning. Another treatment for binocular vision or strabismus problems is visual training. This part of the brain is changeable especially before the teenage years. Proven therapy can alleviate asthenopia, if caused by binocular vision disorders. Frequently, there is a mechanism in which uncorrected farsighted power causes the eyes to cross, compounding the problem. This is called accomodative esotropia and is easily fixed with proper glasses.
Controlling the visual environment is also effective in relieving asthenopia. Poor light, bad ergonomic posture, and inappropriate near working distance can be culprit s for eyestrain. Generally speaking, reading material should be at least 15 inches away. Computer working distance should be 15 to 30 inches away dependent on the size of the screen. Fixating on a computer screen, smart phone, or book for longer than 20 minutes at a time causes eyestrain. An alternate task, such as looking far away, refreshes the focusing muscles of the eye. Studies show people blink less while using computers. This leads to dry eye and again the dreaded asthenopia.
Eye muscle surgery is likely to be reserved for large amounts of strabismus or binocular vision disorders. It works best at a very young age. It is often done for cosmetic purposes. Proper alignment and focus can help for depth perception leading to better driving and sports activity. Regular eye examinations are the simple fix for asthenopia problems. Following guidelines for each
specific deficiency can alleviate most of the unique visual symptoms.
Dr. Steve Belanger is the optometrist owner of Peak Vision in Dillon Colorado. He is a 1982 graduate of the Michigan College of Optometry with undergraduate work at Central Michigan University and Michigan State University. Dr. Belanger relocated from Toledo, Ohio to Dillon in 2015 and resides in Keystone full time. His hobbies are skiing, golfing, cycling, and guitar.
(970) 468-6591 or visit PeakVision1.com